Abstract: With the rapid growth of installed capacity of wind power generation,the operation and maintenance workload of wind turbines is also increasing day by day,but there is still a lack of effective fault detection and diagnosis methods.Based on a brief description of the structure and their fault characteristics of the wind turbines,the existing condition monitoring and fault diagnosis methods of gear boxes,blades and generators and other main fault components of wind turbines are introduced in detail,the shortcomings in the existing condition monitoring and fault diagnosis of wind turbines are summarized and the development direction of monitoring and diagnosis of wind turbines is forecasted.